Sign letter



Jan; 1,1929.

A. w. GAST SIGN LETTER Filed Dec. 26, 1924 3 Sheets-Sheet 1 A. W. GAST SIGN LETTER Jan. 1,1929.

. Filed Dec. 26; 1924 3 Sheets-Sheet 2 Giza t,

Jan. 1; 1929. v 1,697,501

7 A. w. GAST v SIGN' LETTER Filed Deb. 26, 1924 Patented Jan. 1,1929.

Fran

ADOLPH W. GAST, OF CHICAGO, ILLINOIS, ASSIGNOR TO CI-IICAGO MINIATURE LAMP f OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

worms,

Application filed SIGN LETTER.

This invention relates to a novel and improved sign letter or character and consists of the matters hereinafter described and more particularly pointed out in the appended claim.

The invention relates to an illuminated sign lined by exposed lamps and includes a translucent letter plate, either flat or raised to outline the character or plate or equivalent means letter, with a stencil for blocking out and defining the letter or character on the plate. erably made The letter plate enerally and prefof what is commonly known as opal glass, which is a translucent, milk-white of such density as and brilliantly illumin the part where the rays to transmit light rays ate the glass plate in are transmitted, while preventing the bright glow of the illuminating means from for the purpose of as well as for a night able.

Signs of the kind a structed consist of an elongated box with one or both of its long sides plate which outlines the letter plates secured thereto that where raised letters are with the glass in such manner being visible through the glass. The plate is sometimes colored,.but' brilliancy in a day sign,

sign, white is prefers now generally concontaining the stencil letters or. characters,

used, the letter strokes project through the stencil plate; and with electric light bulbs in suficient numbercontained within the box to properly illuminate the sign,

Signs of the kind, while eflective when first put out, soon lose their brilliancy. Being exposed to the weather,

come soiled, both on the the letter plates beinner faces and on the outer faces of the character strokes, so that the letters soon become dull and dark on account of the obstruction to the transmission of light due to the accumulation of dust and soot on the inner and outer faces of the plate, and on account of the reduction of reflecting capacity of the inner face be washed, but a thor- The letter plates may ough cleaning of is almost impossible an not impossible, to rest the inner of the letter plate.

faces of the plates it is very difficult, if

the original brilliancy of such a sign by mere washing. In

any case, the necessity for frequent washing December 26, 1924. Serial No. 757,980.

and cleansing of the sign plates adds greatly to the expense of the upkeep of the sign.

Again, the brilliancy of the sign is affected ter plate of the kind above described, which unit is individuallyilluminated and which ma used in any assembly or arrangement of units of similar kind to'provide a sign upon an ordinary. board or other support. The novel unit is entirely enclosed and sealed so that it is impervous to dust, soot and moisture and is not subject to changes or deterioration by reason of weather conditions.

The novel letter or character unit includes as an illuminating device, an electric lamp or globe which will produce a maximum of light diffusion with a minimum of light concentration, so that the said lamps may be brought comparatively close to the letter plates with a resulting reduction in the wattage consumed by the'lamps and a substantial reduction in the depth of the letter unit casing or enclosure so that the units may be used to make either double or single face signs without presenting excessive depth or width between the faces of the sign.

These and other advantages of my inven Figure 5 1s a view on the same scale as Figures 3 and 4, representmg a partial sec- Figure 9 is a view representing a side ele-- vation of the same.

Figure 10 is a perspective View on a somewhat smaller scale of the shell or casing of the unit shown in Figures 8 and 9.

Figure 11 is a'perspective view of aletter plate with a raised letter therein.

Figure 12is a perspective View of a letter plate which is flat.

Figure 13 is a view'represent'ing a transverse section through another modified form of the invention.

' Referringnow to that embodiment of the invention illustrated in the drawings: 20 indicates a shallow box or casing having a top wall 2l, a bottom wall 22 and'a back Wall 28. Said casing is open on its front side, which is closed as will presently appear, by the letter plate. This casing forms the body of the unit, and is of'such lateral and vertical dimensions as may be required by the size of the letter plate.

The unit is generally intended to contain but a single letter or character; but this will depend upon the size of. the letter or character and also upon the manner in which the unit is to be used. As shown in the drawings, I have presentedithe unit ascontaining but a single letter or character, as will be the case where V the letters or characters are of large dimensions.

24 indicates the letter plate. As illustrated, this is the familiar white, translucent glass plate, preferably opalglass, and as shown bears a raised letter or character 25 which presents a convex outline toward the front or face of'ithe unit, and. a concave outline toward the interior of the unit. The letter plate is supported in any convenient manner at the open side of the casing 2(),in this case, being supported against an openframe 26, the members of which are made in the form of an angle bar with a flange 27' in a vertical plane, against which the marginal part of the letter plate is secured, and a flange 28'at right angles to the vertical flange, which is secured by rivets or otherwise to the bottom, side and top walls of the box or shell 20 in a position adjacent the open front thereof.

The edges 29 of the letter plate fit loosely within the marginal parts 30 of the walls of the casing and are held and sealed therein against the entrance ofv dust, soot and moisture in any suitable manner as for example by a hard, quick drying wax or gum 29 (see Figure 4), together'with packing or not as may be required to seal the joint and to replate will then be entirely coatedor covered tain it in sealed relation under the Weather conditions to which it is apt to be exposed. The sealing'wax or gum should be of such character that it has, when set, the required elasticity to take up any expansion of the letter 'plate or other parts. Preferablya gum which will soften when: heat is used, since manifestly such gum will yield when the letter plate expands upon a rise of temperature.

The-front face of the letter plate as shown in Figures 1 to 7 inclusive are without covering'or coating; But" when-assembled in a sign, the character strokes25 of. the letter may be: outlined or defined in any suitable or wellknown manner, either by opaque paint, or by a thin sheet metal stencil plate which will-be placed in the position. indicated by dotted lines at 31. Thus, the'outer faceof t'he'l'e-tter so that it is impervious to'the'transmission of ight rays, except thepart. or parts which constitute the stroke or strokes ofthe let-ten. The outer face of the letter plate may be other wise treated to present theletter strokes on. a distinctly contrasting-back ground. The walls of the-casing 20; and the inside:

face of the letter plate arecoated with whiteor other reflecting paint which will substantially obstruct the transmission of the-light and reflect substantially all light rays direct-- ed against it: This is important as every part of the inside surface of the unitsliould constitute an eflicient reflecting surface.- This greatly adds t'o'the brilliant effect ofthe-let-- ter or character. The'only exception to this, is that part of theletterplate which const-i tutes the stroke or strokes of the letter or character, na1nely,.thepart 32; This part is not only not painted, but the glossy surface theglass plate, as'when-opahglassis used, is sand blasted or otherwise treated soasto prevent any possibility ofa reflect-ionof tlie'lightwithin the unit' from the back orinner surface ofthe parts constituting tlle'st rokes of the letter orcharacterr In this wayevery bit of light which'reaches thestrokes istransmitted and little or none of it is Post by reflection. On the other hand, by painting'the-inner face of the glass plate on the parts not coveredv by the strokes of theletteror' character, as above set' forth, no. light rays are lost by absorption. in the glass plate; Thus, the full efiiciency, both hydirect transmission and by reflection. of thelight within the unit is concentrated upon and transmitted through the letter strokes; V

The tone or color of the reflecting paint affects the color of the letter; Thus when a white letter is desired a perfectly wliite re 1525 fleeting surface, whether painted or otherwise,is essential forthe most'brilliant effect. A paint which will not oxidize'and turn yel low is desirable. Thus suitable coloring'of the inner reflecting surfaces ofthe sign acts in aid of the coloring effect in the letter stroke when color is used.

The preferred lamp used in the unit is one of low wattage consumption adapted to produce. a minimum of light diffusion with a minimum of light concentration. A lamp of the kind also distributes the heat instead of concentrating it, which is important since the unit, being enclosed and sealed, there is no escape for the heat of the lamps by ventilation as in other signs, but only by conduct-ion from the walls of the unit to the atmosphere.

' Such a. lamp is indicated at 33. Said lamp its of the opening 38 consist-s in its preferred form of an elongated tube or bulb 34 of comparatively small diameter and of substantially the length of the distance between the top and bottom walls 21, 22 of the unit casing, with a. plurality of longitudinally spaced small filaments 35 located therein. The tube is mounted on an elongated insulation back 36 which contains the conductor wires (not shown). Said wires are led forth from one end of the base, the top as shown,to a lamp cord 37. An opening 38 is made in the top or bottom wall of the casing, (in this case, the top wall 21), for. the introduction of the lamp, which is supported in position by a plate or base 39 which proiects as a. flange on all sides beyond the limso as to rest upon said top wall and support the depending lamp within the casing. The base plate 39 is removably secured to the top wall 31 in any convenient manner as by butterfly nuts and screws 40, with a washer 41 interposed between the plate 39 and the said top wall'to sealthe lamp within the casing.

A lamp of the kind best adapted for use in the improved unit is shown and described in Letters-Patent Number 1,043,821, granted to me on the 12th day of November, 1912.

Depending upon the character or letter embodied in the unit, one or more'of such lamps are used. As shown, in the drawings, two lamps are provided and are generally required in the unit for proper diffusion. These lamps may be placed comparatively close to the letter plate without any danger of the reddish glow of the filaments being observable through the strokes of the letter or character. Since they may be placed thus close, the current required to supply the lamps is of greatly reduced wattage as compared to that required in the ordinary incandescent lamps now used in illuminated signs where the lamps are necessarily placed a further distance away in order to get proper distribution. Lamps of the kind have a much longer life owing to the fact that it is not necessary to heat the filaments to such high incandescence as in the case of other lamps. As the lamp globe itself may be placed so near to the letter plate, the depth of the sign unit from the glass plate to the back wall is made comparatively small.

The lamps may be placed, as shown in Figure 6, so as to cast the light directly through the letter strokes, as indicated by the broken lines in said figure, or the lamps may bereversed with their backs toward the letter plate, as indicated at 33 Figure 7 so that the illumination of the strokes is entirely by reflection or indirect lighting, as indicated by the broken lines. In this case, but a single lamp is required for proper diffusion. such case also there is no possibility whatever of the glow of the lamps being observable through the letter strokes, even when glass of lesser density than the opal glass is used for the letter plate. The arrangementof the lamps in this Way makes it possible to use standard lamp globes of some types, provided with a suitable back or backing, in a comparatively shallow unit casing, Without danger of the glow servable through the strokes of the letter.

As hereinbefore mentioned, the letter plate may be either one which bears raised letters or it may be flat, in either case, however, being made of the required density. The raised letter plate 24 of familiar construction is shown in perspective in Figure 11, wherein the treatment of the inner face of the letter plate throughout the strokes of the letter or character is indicated by the dots 42, which show where the plate has been sand blasted or otherwise treated to remove the gloss and destroy its reflecting character. A fiatletter plate 24 that is one without a. raised letter, is shown in perspective in Figure 12. Here again the plate istreated on its inside face throughout the stroke of the: letter or character as indicated by the dots 43 to remove the gloss by sand blasting or otherwise. The rear surface of the letter stroke treated in this manner also acts to finally break up and distribute the light rays, thereby removing the last possibility of concentration.

The letter unit may be provided with any desirable flanges or base suitable for assembling it with like units and mounting it upon a proper support as a signboard or the like. In Figures 1 and '2, angular brackets 44, 44 are attached to the top and bottom walls of the unit casing at the front-thereof by meansof which the unit may be conveniently secured at top and bottom to an open frame (not shown) which is designed to provide a support for the units, and which includes the familiar stencil plate indicated by the dotted lines 31 in Figure 4.

In Figures 8 to 10 inclusive, a. somewhat modified form of the unit. In this case 2O indicates the unit and 25 the letter plate, other corresponding parts being indicated by numerals like those usedin first describing the unit but with the superfix X. The unit shell is provided at its front open side with a recessed, marginal open frame 45 to receive the letter plate. 46 indicates the of the filament being ob- I have shown i shouldersr'48',andbeing'sealedas before. The

shoulder 48 is somewhat greater in deptltthani, thethicknessofthe letter plate-,rso that saidplate is set back from the face 49. of the: frame-45'. V I

The letterplate is painted on its outer face except at the letter strokes in order to block? out the letters so that the unitinlthis instance is ready for assembly wit-h others on. a suitable'support by means of horizontal flanges. 50, 50 at the-top; anch bottom of: the frame 4'5; without the use of: astencilplate; This 'consstructionissometimes preferred; since the absence-of the stencil: plate-eliminates the possi. bility of water or moisture avhether. fromxthe- Weatheii' or from= washing, gettingbetween the letter plate-and therstencilplate;when:it is likely to causerust and ini time. produce ruststreaks tom antheface ofthe let-ter: plate. In theunits-hereinbefore described, a let ter plateis used upon but theone side-ofthe. unit,.and this is the-manner in:which:the:unit will generally be made'inz order tomeet all conditions in: botliisingle and: double: face signs; In some:cases- .however, t-l1eback:clo-

sure of the: unit easing as well: as: theif-rontclosure, may be prouidediby. a letter plate'in. which case thexunit itself willbe double face with a. letter. plate-presented on both faces.

Such a modification of the. letter unit is shown in Figure 13 wherein like-parts are all indicated; by likernumeralsx with the superfix y; 51 indicates the additional letter plate which forms the back closure of the casing;

earner V. Said letter plate is mounted and sealed Within the margins of thevtop bottom and side Walls of the casing. at the back in the same way as the letter plate -is-mountedand sealed therein at thefront, as; heretofore de scribed. In this case the lamps 33 have their insulation backs 33 if such backs be used", turned to-Wardsthe side-walls of the casing.

While in: describing. my invention, I have referred to many details ofvform and: of me.- chanical construct-ion andarrangement ofparts, it is to-be understood that the inven tionis in no way limited thereto,-- except asmay be pointed. out in the appended claim.

I claim asmy invention An illuminated sign letter unit comprising a shallow casing: closed'onall-sides but open in front a translucent glass letter plateclosing theopen front of said casing,;means for sealing the edges of said letter plate in saidcasing, said means b-eingadapted to take. up the expansion of said'plateunder changes'of temperature, and a removable lamp of low candle power but of Wide diffusion sealedin said casing but removable therefrom, the candle power of said lamp andithe density of said letter plate being so correlated to the depth of said casing and to each other that said letter plate Will be'brilliantly and evenly illuminated without concentration of direct light at any point or points of said letter strokes, and means for removably supporting and sealing said lamp in said casing.

In testimony that I claim the foregoing. as my invention I afiix my signature this-22d day of Dece1nber, A 11.- 1924.

ADOLPH GAST. 

